package com.bxd.baodan.util;

import java.io.UnsupportedEncodingException;
import java.security.Key;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.spec.AlgorithmParameterSpec;

import javax.crypto.Cipher;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.IvParameterSpec;



import android.util.Base64;

/**
 * 加密解密工具包
 * 
 * @author Winter Lau
 * @date 2011-12-26
 */
public class DesUtil {

	public static final String KEY = "SqqjlWE7";
	public static final String ALGORITHM_DES = "DES/CBC/PKCS5Padding";
	/**
	 * MD5加密算法
	 * @param string
	 * @return
	 */
	public static String md5(String string) {
		byte[] hash;
		try {
			hash = MessageDigest.getInstance("MD5").digest(
					string.getBytes("UTF-8"));
		} catch (NoSuchAlgorithmException e) {
			throw new RuntimeException("Huh, MD5 should be supported?", e);
		} catch (UnsupportedEncodingException e) {
			throw new RuntimeException("Huh, UTF-8 should be supported?", e);
		}

		StringBuilder hex = new StringBuilder(hash.length * 2);
		for (byte b : hash) {
			if ((b & 0xFF) < 0x10)
				hex.append("0");
			hex.append(Integer.toHexString(b & 0xFF));
		}
		return hex.toString();
	}
	/**
	 * 加密
	 * @param data
	 * @return
	 */
	public static String encode(String data) {
		try {
			return encode(KEY, data);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return "";
	}
	/**
	 * 解密
	 * @param data
	 * @return
	 */
	public static String decode(String data) {
		return decodeValue(KEY, data);
	}

//	/**
//	 * DES算法，加密
//	 * 
//	 * @param data
//	 *            待加密字符串
//	 * @param key.jks
//	 *            加密私钥，长度不能够小于8位
//	 * @return 加密后的字节数组，一般结合Base64编码使用
//	 * @throws InvalidAlgorithmParameterException
//	 * @throws Exception
//	 */
//	public static String encode(String key.jks, String data) {
//		if (data == null)
//			return null;
//		try {
//			DESKeySpec dks = new DESKeySpec(key.jks.getBytes());
//			SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
//			// key的长度不能够小于8位字节
//			Key secretKey = keyFactory.generateSecret(dks);
//			Cipher cipher = Cipher.getInstance(ALGORITHM_DES);
//			IvParameterSpec iv = new IvParameterSpec(key.jks.getBytes());
//			AlgorithmParameterSpec paramSpec = iv;
//			cipher.init(Cipher.ENCRYPT_MODE, secretKey, paramSpec);
//			byte[] bytes = cipher.doFinal(data.getBytes());
//			return byte2hex(bytes);
//		} catch (Exception e) {
//			e.printStackTrace();
//			return data;
//		}
//	}
//
//	/**
//	 * DES算法，解密
//	 * 
//	 * @param data
//	 *            待解密字符串
//	 * @param key.jks
//	 *            解密私钥，长度不能够小于8位
//	 * @return 解密后的字节数组
//	 * @throws Exception
//	 *             异常
//	 */
//	public static String decode(String key.jks, String data) {
//		if (data == null)
//			return null;
//		try {
//			DESKeySpec dks = new DESKeySpec(key.jks.getBytes());
//			SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
//			// key的长度不能够小于8位字节
//			Key secretKey = keyFactory.generateSecret(dks);
//			Cipher cipher = Cipher.getInstance(ALGORITHM_DES);
//			IvParameterSpec iv = new IvParameterSpec(key.jks.getBytes());
//			AlgorithmParameterSpec paramSpec = iv;
//			cipher.init(Cipher.DECRYPT_MODE, secretKey, paramSpec);
//			return new String(cipher.doFinal(hex2byte(data.getBytes())));
//		} catch (Exception e) {
//			e.printStackTrace();
//			return data;
//		}
//	}
//
//	/**
//	 * 二行制转字符串
//	 * 
//	 * @param b
//	 * @return
//	 */
//	private static String byte2hex(byte[] b) {
//		StringBuilder hs = new StringBuilder();
//		String stmp;
//		for (int n = 0; b != null && n < b.length; n++) {
//			stmp = Integer.toHexString(b[n] & 0XFF);
//			if (stmp.length() == 1)
//				hs.append('0');
//			hs.append(stmp);
//		}
//		return hs.toString().toUpperCase(Locale.getDefault());
//	}
//
//	private static byte[] hex2byte(byte[] b) {
//		if ((b.length % 2) != 0)
//			throw new IllegalArgumentException();
//		byte[] b2 = new byte[b.length / 2];
//		for (int n = 0; n < b.length; n += 2) {
//			String item = new String(b, n, 2);
//			b2[n / 2] = (byte) Integer.parseInt(item, 16);
//		}
//		return b2;
//	}
	

	/**
	 * DES算法，加密
	 *
	 * @param data
	 *            待加密字符串
	 * @param key
	 *            加密私钥，长度不能够小于8位
	 * @return 加密后的字节数组，一般结合Base64编码使用
	 * @throws CryptException
	 *             异常
	 */
	public static String encode(String key, String data) throws Exception {
		return encode(key, data.getBytes());
	}

	/**
	 * DES算法，加密
	 *
	 * @param data
	 *            待加密字符串
	 * @param key
	 *            加密私钥，长度不能够小于8位
	 * @return 加密后的字节数组，一般结合Base64编码使用
	 * @throws CryptException
	 *             异常
	 */
	public static String encode(String key, byte[] data) throws Exception {
		try {
			DESKeySpec dks = new DESKeySpec(key.getBytes());

			SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
			// key的长度不能够小于8位字节
			Key secretKey = keyFactory.generateSecret(dks);
			Cipher cipher = Cipher.getInstance(ALGORITHM_DES);
			IvParameterSpec iv = new IvParameterSpec(key.getBytes());
			AlgorithmParameterSpec paramSpec = iv;
			cipher.init(Cipher.ENCRYPT_MODE, secretKey, paramSpec);

			byte[] bytes = cipher.doFinal(data);

			return Base64.encodeToString(bytes, Base64.DEFAULT);
		} catch (Exception e) {
			throw new Exception(e);
		}
	}

	/**
	 * DES算法，解密
	 *
	 * @param data
	 *            待解密字符串
	 * @param key
	 *            解密私钥，长度不能够小于8位
	 * @return 解密后的字节数组
	 * @throws Exception
	 *             异常
	 */
	public static byte[] decode(String key, byte[] data) throws Exception {
		try {
			SecureRandom sr = new SecureRandom();
			DESKeySpec dks = new DESKeySpec(key.getBytes());
			SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
			// key的长度不能够小于8位字节
			Key secretKey = keyFactory.generateSecret(dks);
			Cipher cipher = Cipher.getInstance(ALGORITHM_DES);
			IvParameterSpec iv = new IvParameterSpec(key.getBytes());
			AlgorithmParameterSpec paramSpec = iv;
			cipher.init(Cipher.DECRYPT_MODE, secretKey, paramSpec);
			return cipher.doFinal(data);
		} catch (Exception e) {
			throw new Exception(e);
		}
	}

	/**
	 * 获取编码后的值
	 * 
	 * @param key
	 * @param data
	 * @return
	 * @throws Exception
	 */
	public static String decodeValue(String key, String data) {
		byte[] datas;
		String value = null;
		try {
			if (System.getProperty("os.name") != null
					&& (System.getProperty("os.name").equalsIgnoreCase("sunos") || System
							.getProperty("os.name").equalsIgnoreCase("linux"))) {
				datas = decode(key, Base64.decode(data, Base64.DEFAULT));
			} else {
				datas = decode(key, Base64.decode(data, Base64.DEFAULT));
			}

			value = new String(datas);
		} catch (Exception e) {
			value = "";
		}
		return value;
	}

}